It's a chemical change because bonds are being broken and formed.
The question is in complete, the complete question is:
Which element has an outer electron configuration of s
2
p4
?
(A) Ca (B) Cr (C) Ge (D) Se
Answer:
(D) Se
Explanation:
The outer electronic configuration of an atom reflects the group to which it belongs in the periodic table. Each group has its unique outermost electron configuration and number of electrons found in the outermost shell of the atoms of elements in the group.
s
2
p4 is the unique outermost electron configuration of group 16 elements. Group 16 elements have six electrons in their outermost shell. If we consider the options, only Se is a member of group 16. Hence it is only Se that has the outermost electron configuration s
2
p4
.
B. Fossil
Why? Well skeleton seems like another answer BUT the definition of a fossil is an imprint of an organism on rock.
Example: A dinosaur presses it’s foot in dirt and it leaves a footprint or ‘fossil’ behind
The correct answer is: [A]:
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"one atom transfers an electron to another atom" .
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"An ionic bond is formed when <u> one atom transfers an electron to another atom </u>."
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